/*
 * PostgreSQL plugin. 
 * $Id$
 */

#define IN_PLUGIN
#include "../../echoping.h"

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifdef POSTGRESQL_PREFIX
#include <postgresql/libpq-fe.h>
#else
#include <libpq-fe.h>
#endif

const char *request = NULL;
int readall = FALSE;
int connect_each_time = FALSE;
poptContext postgresql_poptcon;
PGconn *conn;
PGresult *res;
char *conninfo;
echoping_options global_options;

void
postgresql_usage (const char *msg)
{
  if (msg)
    {
      printf ("PostgreSQL plugin error: %s\n", msg);
    }
  poptPrintUsage (postgresql_poptcon, stdout, 0);
  fprintf (stderr, "  [SQL-request]\n");
  exit (1);
}

char *
init (const int argc, const char **argv,
      const echoping_options global_external_options)
{
  int value;
  char *msg = malloc (256);
  char *rest;
  /* popt variables */
  struct poptOption options[] = {
    {"conninfo", 'c', POPT_ARG_STRING, &conninfo, 0,
     "Connection information for the Postgresql server. Something like 'host=foo dbname=bar''",
     ""},
    {"readall", 'a', POPT_ARG_NONE, &readall, 0,
     "Read all the data sent by the Postgresql server",
     ""},
    {"connect-each-time", 'e', POPT_ARG_NONE, &connect_each_time, 0,
     "(Re)Connect to the Postgresql server at each iteration",
     ""},
    POPT_AUTOHELP POPT_TABLEEND
  };
  global_options = global_external_options;
  if (global_options.udp)
    err_quit ("UDP makes no sense for a PostgreSQL connection");
  postgresql_poptcon = poptGetContext (NULL, argc,
				       argv, options,
				       POPT_CONTEXT_POSIXMEHARDER);
  while ((value = poptGetNextOpt (postgresql_poptcon)) > 0)
    {
    }
  if (value < -1)
    {
      sprintf (msg, "%s: %s",
	       poptBadOption (postgresql_poptcon, POPT_BADOPTION_NOALIAS),
	       poptStrerror (value));
      postgresql_usage (msg);
    }
  request = poptGetArg (postgresql_poptcon);
  if (request == NULL)
    request = "SELECT now()";
  rest = poptGetArg (postgresql_poptcon);
  if (rest != NULL)
    postgresql_usage ("Erroneous additional arguments");
  if (conninfo == NULL)
    conninfo = "";
  return NULL;			/* We only use the conninfo, echoping does not see our hostname or port */
}

void
start_raw ()
{
  if (!connect_each_time)
    {
      conn = PQconnectdb (conninfo);
      if (conn == NULL)
	{
	  err_quit ("Cannot create connection\n");
	}
      if (PQstatus (conn) == CONNECTION_BAD)
	{
	  err_quit ("Connection failed: %s\n", PQerrorMessage (conn));
	}
    }
}

int
execute ()
{
  unsigned int row, column;
  char *result;
  if (connect_each_time)
    {
      conn = PQconnectdb (conninfo);
      if (conn == NULL)
	{
	  err_ret ("Cannot create connection\n");
	  return -1;
	}
      if (PQstatus (conn) == CONNECTION_BAD)
	{
	  err_ret ("Connection failed: %s\n", PQerrorMessage (conn));
	  return -1;
	}
    }
  res = PQexec (conn, request);
  if (PQresultStatus (res) != PGRES_TUPLES_OK)
    {
      err_ret ("Cannot run \"%s\": %s\n", request,
	       PQresultErrorMessage (res));
      return -1;
    }
  if (global_options.verbose)
    printf ("%d tuples returned\n", PQntuples (res));
  if (readall)
    {
      for (row = 0; row < PQntuples (res); row++)
	{
	  for (column = 0; column < PQnfields (res); column++)
	    {
	      result = PQgetvalue (res, row, column);
	      if (result == NULL)
		{
		  err_ret ("Cannot retrieve value [%d,%d]\n", row, column);
		  return -1;
		}
	      /* else {
	         printf ("DEBUG: [%d,%d] %s\n", row, column, result);
	         } */
	    }
	}
    }
  if (connect_each_time)
    PQfinish (conn);
  return 0;
}

void
terminate ()
{
  if (!connect_each_time)
    PQfinish (conn);
}